Processes of increasing crystallinity alignment of protein films and products thereof

Abstract

A method of processing a protein in an acid solution is disclosed. The processed protein exhibits various optimized properties including crystallinity, thermal stability, bio-stability, and elastic modulus.

The invention claimed is: 
     
       1. A method of processing a protein, the method comprising:
 a) dissolving a protein in a solution comprising an acid and a salt of at least one of an alkaline earth metal and an alkali metal, to yield a protein solution; 
 b) removing the acid from the protein solution to yield a processed protein; 
 c) compressing the processed protein by applying pressure in the range of about 10 lb/sq. in to about 500,000 lb/sq. in. to yield a compressed protein;
 wherein the protein solution further comprises a non-proteinaceous material selected from the group consisting of polymers, ceramics, glasses, composites, metals, alloys, and any combinations thereof. 
 
 
     
     
       2. The method of  claim 1 , wherein removing the acid from the protein solution comprises evaporating the acid from the protein solution. 
     
     
       3. The method of  claim 1 , wherein the acid is selected from the group consisting of formic acid, acetic acid, hydrochloride acid, propionic acid, butyric acid, valeric acid, caproic acid, oxalic acid, lactic acid, malic acid, citric acid, benzoic acid, carbonic acid, phenol, uric acid, and any combinations thereof. 
     
     
       4. The method of  claim 1 , wherein the salt is selected from the group consisting of calcium chloride, calcium fluoride, calcium bromide, calcium iodide, calcium citrate, calcium gluceptate, calcium gluconate, calcium hydroxide, calcium lactate, calcium phosphate, calcium propionate, calcium acetate, and calcium carbonate. 
     
     
       5. The method of  claim 1 , wherein the protein is from a source selected from the group consisting of silks, corn zeins, collagens, elastins, keratins, resilins, reflectins, plant and soy proteins, and any combinations thereof. 
     
     
       6. The method of  claim 1 , wherein the protein is a natural protein. 
     
     
       7. The method of  claim 1 , wherein the protein is a recombinant protein. 
     
     
       8. The method of  claim 1 , further comprising adding to the protein solution one or more agents selected from the group consisting of graphene, nanotubes, nanofibers, nanoparticles, metal particles, a chemical agent, and a pharmaceutical agent. 
     
     
       9. The method of  claim 1 , wherein the protein solution contains about 0.5-10% salt (w/v). 
     
     
       10. The method of  claim 1 , wherein the protein solution contains about 0.5% to about 50% (w/v) of the protein. 
     
     
       11. The method of  claim 1 , wherein the processed protein is soaked in water prior to being compressed. 
     
     
       12. The method of  claim 1 , wherein the pressure is selected to optimize at least one protein characteristic selected from the group consisting of solvent release temperature, thermal degradation temperature, crystallinity, bio-stability, elastic modulus, and any combinations thereof. 
     
     
       13. A processed protein produced by the method of  claim 1 . 
     
     
       14. The processed protein of  claim 13 , wherein the processed protein exhibits a higher crystallinity relative to its unprocessed form. 
     
     
       15. The processed protein of  claim 13 , wherein the processed protein is insoluble in water. 
     
     
       16. The processed protein of  claim 13 , wherein the processed protein has about 1% to about 70% higher β-sheet content than the unprocessed protein. 
     
     
       17. The processed protein of  claim 13 , wherein the processed protein exhibits a red-shift in absorbance wavelength (to a lower frequency) relative to the unprocessed protein. 
     
     
       18. The method of  claim 1 , wherein any insoluble material or impurities are separated from the protein solution before the acid is removed from the protein solution. 
     
     
       19. The method of  claim 1 , wherein the protein solution is allowed to stand for about 2 mins. to about 8 mins. before the acid is removed from the protein solution. 
     
     
       20. The method of  claim 1 , wherein the pressure is applied to the processed protein for about 30 seconds to about 24 hours. 
     
     
       21. The method of  claim 1 , wherein the processed protein has higher crystallinity than the unprocessed protein. 
     
     
       22. The method of  claim 1 , wherein the processed protein has about 1% to about 70% higher β-sheet content than the unprocessed protein. 
     
     
       23. The method of  claim 1 , wherein the compressed protein is further dried. 
     
     
       24. A method of processing a protein, the method comprising:
 a) dissolving a protein in a solution comprising an acid and a salt of at least one of an alkaline earth metal and an alkali metal, to yield a protein solution; 
 b) removing the acid from the protein solution to yield a processed protein; 
 c) compressing the processed protein by applying pressure in the range of about 10 lb/sq. in to about 500,000 lb/sq. in. to yield a compressed protein; 
 wherein the protein is a recombinant protein. 
 
     
     
       25. The method of  claim 24 , wherein removing the acid from the protein solution comprises evaporating the acid from the protein solution. 
     
     
       26. The method of  claim 24 , wherein the acid is selected from the group consisting of formic acid, acetic acid, hydrochloride acid, propionic acid, butyric acid, valeric acid, caproic acid, oxalic acid, lactic acid, malic acid, citric acid, benzoic acid, carbonic acid, phenol, uric acid, and any combinations thereof. 
     
     
       27. The method of  claim 24 , wherein the salt is selected from the group consisting of calcium chloride, calcium fluoride, calcium bromide, calcium iodide, calcium citrate, calcium gluceptate, calcium gluconate, calcium hydroxide, calcium lactate, calcium phosphate, calcium propionate, calcium acetate, and calcium carbonate. 
     
     
       28. The method of  claim 24 , wherein the protein is from a source selected from the group consisting of silks, corn zeins, collagens, elastins, keratins, resilins, reflectins, plant and soy proteins, and any combinations thereof. 
     
     
       29. The method of  claim 24 , wherein the protein solution further comprises a non-proteinaceous material. 
     
     
       30. The method of  claim 29 , wherein the non-proteinaceous material is selected from the group consisting of polymers, ceramics, glasses, composites, metals, alloys, and any combinations thereof. 
     
     
       31. The method of  claim 24 , further comprising adding to the protein solution one or more agents selected from the group consisting of graphene, nanotubes, nanofibers, nanoparticles, metal particles, a chemical agent, and a pharmaceutical agent. 
     
     
       32. The method of  claim 24 , wherein the protein solution contains about 0.5% to about 50% (w/v) of the protein. 
     
     
       33. The method of  claim 24 , wherein the processed protein is soaked in water prior to being compressed. 
     
     
       34. The method of  claim 24 , wherein the pressure is selected to optimize at least one protein characteristic selected from the group consisting of solvent release temperature, thermal degradation temperature, crystallinity, bio-stability, elastic modulus, and any combinations thereof. 
     
     
       35. The method of  claim 24 , wherein any insoluble material or impurities are separated from the protein solution before the acid is removed from the protein solution. 
     
     
       36. The method of  claim 24 , wherein the protein solution is allowed to stand for about 2 mins. to about 8 mins. before the acid is removed from the protein solution. 
     
     
       37. The method of  claim 24 , wherein the pressure is applied to the processed protein for about 30 seconds to about 24 hours. 
     
     
       38. The method of  claim 24 , wherein the processed protein has higher crystallinity than the unprocessed protein. 
     
     
       39. The method of  claim 24 , wherein the processed protein has about 1% to about 70% higher β-sheet content than the unprocessed protein. 
     
     
       40. The method of  claim 24 , wherein the compressed protein is further dried.